David W. Wetter

Theory as Mediating Variables: Why Aren't Community Interventions Working as Desired?

Purpose: This paper discusses the role of theory in explaining why recent community intervention trials for chronic disease prevention are not achieving the level of desired behavioral effects and related outcomes. Method: Literature review and analysis are used to derive an explanation. Results: All interventions (e.g., school nutrition education) effect change in behavioral outcomes (e.g., dietary behaviors) through mediating variables. Selected from the social and behavioral theories, these mediating variables can be environmental (e.g., increased availability of the targeted food) or intrapersonal (e.g., increased self-efficacy for eating the targeted foods). The percentage of variance of the outcome variables accounted for by the mediating variables has been modest to low. This places one limit on how much change interventions can achieve in outcomes. Another limit is imposed by the ability of the interventions to produce change in the mediating variables, which also has been weak. Conclusions: More basic research should examine: (i) the relationships between mediating variables and behavior; and (ii) how interventions effect change in mediating variables. One possible six phase process for developing such research is described.

Predicting relapse back to smoking: Contrasting affective and physical models of dependence

Traditional models of physical dependence suggest that nicotine dependence should be reflected by the extent of drug exposure (e.g., smoking rate) and by evidence of physiological adaptation (e.g., withdrawal severity). An affective model suggests that nicotine dependence should be related to an individuals tendency to experience negative affect and expectations that nicotine use would ameliorate such affect. This research investigated the ability of these 2 models to predict relapse back to smoking at 6 months postquit. Logistic regression models were developed and tested in 505 heavy smokers participating in nicotine patch clinical trials. Results supported both models, but the most potent predictor of outcome was postquit negative affect, which accounted for much of the predictive validity of traditional measures of nicotine dependence. Affective reactivity appears to be a core constituent of dependence.

Prevalence and predictors of transitions in smoking behavior among college students.

The prevalence of smoking among college students is surprisingly high and represents a significant public health issue. However, there are few longitudinal studies of smoking in this population. This study examined the prevalence and predictors of transitions in smoking behavior among a cohort of 548 college students. Over the course of 4 years, 87% of daily smokers and almost 50% of occasional smokers continued to smoke. Among nonsmokers, 11.5% began smoking occasionally and none became daily smokers. In general, predictors of smoking behavior change were significant only among baseline occasional smokers and included gender, smoking outcome expectancies, and affect regulation expectations. Peer and parental smoking, demographics, affect, stress, and alcohol use were generally not predictive of change. Tobacco control interventions targeted at college students are clearly warranted.

Development and validation of the Wisconsin Smoking Withdrawal Scale.

The accurate assessment of nicotine withdrawal is important theoretically and clinically. A 28-item scale, the Wisconsin Smoking Withdrawal Scale, was developed that contains 7 reliable subscales tapping the major symptom elements of the nicotine withdrawal syndrome. Coefficients alpha for the subscales range from .75 to .93. This scale is sensitive to smoking withdrawal, is predictive of smoking cessation outcomes, and yields data that conform to a 7-factor structure. The 7 scales predicted intratreatment smoking, chi2(7, N = 163) = 15.19, p = .034. Moreover, the questionnaire is sufficiently brief so that it can be used in both clinical and research contexts.

The effects of depressed mood on smoking cessation: Mediation by postcessation self-efficacy

This study evaluated the relationship between precessation depressed mood and smoking abstinence and assessed the mediation of this effect by postcessation self-efficacy, urges to smoke, nicotine withdrawal, and coping behavior. The sample included 121 smokers previously treated in a randomized controlled trial involving behavior therapy and the nicotine patch. The results showed that precessation depressed mood was inversely related to 6-month abstinence. This effect remained significant after controlling for treatment, possible depression history, baseline smoking rates, and several other demographic factors. Postcessation self-efficacy, at the 2-, 4-, and 8-week postquit assessments, was the strongest mediator of the effects of precessation depressed mood on abstinence, accounting for 32%, 38%, and 48% of the effect of mood on abstinence, respectively.

Mechanisms Linking Socioeconomic Status to Smoking Cessation: A Structural Equation Modeling Approach

OBJECTIVE Although there has been a socioeconomic gradient in smoking prevalence, cessation, and disease burden for decades, these disparities have become even more pronounced over time. The aim of the current study was to develop and test a conceptual model of the mechanisms linking socioeconomic status (SES) to smoking cessation. DESIGN The conceptual model was evaluated using a latent variable modeling approach in a sample of 424 smokers seeking treatment (34% African American; 33% Latino; 33% White). Hypothesized mechanisms included social support, neighborhood disadvantage, negative affect/stress, agency, and craving. MAIN OUTCOME MEASURE The primary outcome was Week 4 smoking status. RESULTS As was hypothesized, SES had significant direct and indirect effects on cessation. Specifically, neighborhood disadvantage, social support, negative affect/stress, and agency mediated the relation between SES and smoking cessation. A multiple group analysis indicated that the model was a good fit across racial/ethnic groups. CONCLUSION The present study yielded one of the more comprehensive models illuminating the specific mechanisms that link SES and smoking cessation. Policy, community, and individual-level interventions that target low SES smokers and address the specific pathways identified in the current model could potentially attenuate the impact of SES on cessation.

The Effect of Tobacco Outlet Density and Proximity on Smoking Cessation

OBJECTIVES We examined the influence of tobacco outlet density and residential proximity to tobacco outlets on continuous smoking abstinence 6 months after a quit attempt. METHODS We used continuation ratio logit models to examine the relationships of tobacco outlet density and tobacco outlet proximity with biochemically verified continuous abstinence across weeks 1, 2, 4, and 26 after quitting among 414 adult smokers from Houston, Texas (33% non-Latino White, 34% non-Latino Black, and 33% Latino). Analyses controlled for age, race/ethnicity, partner status, education, gender, employment status, prequit smoking rate, and the number of years smoked. RESULTS Residential proximity to tobacco outlets, but not tobacco outlet density, provided unique information in the prediction of long-term, continuous abstinence from smoking during a specific quit attempt. Participants residing less than 250 meters (P = .01) or less than 500 meters (P = .04) from the closest tobacco outlet were less likely to be abstinent than were those living 250 meters or farther or 500 meters or farther, respectively, from outlets. CONCLUSIONS Because residential proximity to tobacco outlets influences smoking cessation, zoning restrictions to limit tobacco sales in residential areas may complement existing efforts to reduce tobacco use.

Pardon my gaffe : effects of sex, status, and consequence severity on accounts

Examined the effects of offender sex, offender status, and consequence severity on accounts following an embarrassing predicament. Subjects were induced to believe they had committed a gaffe with either relatively mild or severe consequences for a confederate/victim of either higher or lower status than they, and their verbal and nonverbal behaviors captured on videotape served as the source of dependent variable measures

Affect, expectancies, urges, and smoking: Do they conform to models of drug motivation and relapse?

Social-learning models of drug motivation and relapse often include the constructs of affect and drug expectancies. Most research has taken a molar approach to examining relations between these constructs and level of drug use. An experiment examined the roles of affect and expectancies in multiple measures of situation-specific motivation to smoke tobacco. Undergraduate smokers (n = 101) received either a positive or negative mood manipulation (false feedback on an intelligence test). Self-reported urge was influenced by both negative affect and expectancies for positive reinforcement from smoking. Actual consumption was related only to smoking expectancies and only among abstaining smokers. Affect by expectancy interactions were also found. Findings support a limited role of affect and expectancies in smoking motivation. Poor coherence among the motivational indexes challenges the assumptions of existing models of drug motivation.

A Psychometric Evaluation of Cigarette Stimuli Used in a Cue Reactivity Study

Laboratory studies have demonstrated that cigarette smokers react with significant subjective and autonomic responses (e.g., increased craving and increased heart rate) in the presence of stimuli associated with smoking. Although cue reactivity effects are typically robust, a number of methodological considerations make interpretation and design of cue reactivity studies problematic. Previous research has paid scant attention to the psychometric properties of the cigarette cues presented, and standard cues would enhance comparison and synthesis of studies. In the present study, we evaluated 12 cigarette photos (compared with positive, negative, and neutral photos), used in a separate study, for their ability to evoke self-report of craving in both nicotine-deprived and nondeprived smokers. These photos performed as expected, with cigarette pictures evoking significantly higher craving than neutral pictures and deprived smokers showing a trend toward higher craving than nondeprived smokers. The cigarette picture set was evaluated for internal consistency (Cronbachs alpha = .97) as a 12-item scale and further reduced to multiple 2-item scales with reliability estimates ranging from .70 to .93. A cluster analysis of all pictures showed that, when rated for craving, cigarette pictures clustered together, indicating they had distinct properties compared with positive, negative, and neutral pictures. Effect sizes were calculated for each cigarette picture in both deprived and nondeprived smokers. The craving effect sizes ranged from .57 to .98 for nondeprived smokers, and from .61 to .99 for deprived smokers. The analyses suggest these cigarette pictures have excellent psychometric properties for use in future cue reactivity studies.